September 21, 2000
01:00 AM (EDT)

News Release Number: STScI-2000-32

Movies from Hubble Show the Changing Faces of Infant Stars

September 21, 2000: Time-lapse movies made from a series of pictures
taken by NASA's Hubble Space Telescope are showing astronomers that young stars
and their surroundings can change dramatically in just weeks or months. As with
most children, a picture of these youngsters taken today won't look the same as
one snapped a few months from now. The movies show jets of gas plowing into space
at hundreds of thousands of miles per hour and moving shadows billions of miles
in size. The young star systems featured in the movies, XZ Tauri and HH 30, reside
about 450 light-years from Earth in the Taurus-Auriga molecular cloud, one of
the nearest stellar nurseries to our planet. Both systems are probably less than
a million years old, making them relative newborns, given that stars typically
live for billions of years.

Q & A: Understanding the Discovery

1.
How do stars form?

Stars form in clouds of gas and dust that collect into a swirling disk. Outflows of gas, like the bubbles and jets seen in these images, occur when some of the material feeding the infant star from the surrounding disk is diverted away by the star's magnetic field and accelerated out its magnetic poles. These outflows are often squeezed into narrow jets that can extend many light-years away from the star. Such outflows are a common and natural result of stellar birth.